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dpp
24th of November 2004 (Wed), 01:04
Hello

I think maybe I am being stupid or lazy, but can someone please advise about the Canon Wireless system.

Am I correct in thinkI would need 2 or more Flashes (currently I have a 550EX), maybe umbrellas to put these in , and then the Wireless Transmitter thing that controls the slaves etc?
If you use this kind of system is it effective?

dhbailey
24th of November 2004 (Wed), 03:15
I don't use it, but I assume you're speaking of using 2 or more flashes as slaves from a single master like the 550ex or 580ex mounted on the camera.

From your question it sounds as if you think you have to get a separate wireless control unit. You don't need a wireless transmitter as a separate unit -- the flashes themselves contain the necessary electronics for doing all of that, as long as you're using Canon flashes or flashes designed to work with the Canon wireless system.

defordphoto
24th of November 2004 (Wed), 04:54
The Canon system is a bit limited because it's IR. If you need something more robust than that, then you'll have to move into some pocket wizards, which are 2.4gHz I believe. Either way they use radio signals as opposed to IR.

DaveG
24th of November 2004 (Wed), 07:37
Hello

I think maybe I am being stupid or lazy, but can someone please advise about the Canon Wireless system.

Am I correct in thinkI would need 2 or more Flashes (currently I have a 550EX), maybe umbrellas to put these in , and then the Wireless Transmitter thing that controls the slaves etc?
If you use this kind of system is it effective?
You need a 550EX flash or the ST-E2 transmitter as the Master. Then you need at least one more flash either another 550EX or a 420 EX.

I use a 550 as the Master and then have a 420 as the Slave. The ST-E2 does not put out as powerful an instructional pulse so it's range is reduced (weird for a product that has only one function) and of course it's NOT a flash so I can't use it as such if I needed too.

If you are reading the 550's instruction book it implies that the 550 Master cannot be part of a two flash ratioed lighting system, and that the 550 is used as a "projection" device, exactly like a ST-E2. Then you'll infer that you'll need TWO slaved flashes (one being Group A and Group B) to make the wireless TTL work. This is NOT true and the setup is very easy: You set the 420 (or 550 if you choose the more expensive flash) to group B and it will be the Slave. The 550 will default to Group A and will be the Master. You will NOT find these extremely simple instructions anywhere in a Canon publication.

After that you set the 550 to Master and the 420 to Slave. Then with the 550's instruction book in hand you start to work through the back panel controls. You will want to end up at RATIOS. As part of the definition of ratioed lighting, the fill light MUST be within 20 degrees of the camera postion. That way light from the fill reaches both sides of the subject's face. The irony is that the more powerful Master flash - the 550 - becomes the fill light, and the 420 becomes the main light.

The joy of the Canon Wireless system is that you can control these ratios from the camera position by adjusting the 550. I use it all of the time and I'm not locked into any particular ratio, and with digital I can experiment for free.

I have added Velcro strips to the side of the 420 so I can put black cards - flags they're called - to the side of the flash to prevent flare.

The Canon Wireless is also line-of-sight so you can't hide the slave behind something like you could if it was a radio slave. But you can't control the radio slave after you've set it up, except by going to the slave position and making adjustments.

Aunt Gertrude's point and shoot flash will NOT trigger the Canon Wireless slave either so you can use it in places where there are likely to be other cameras present.

What the Canon Wireless System isn't particularly good for is when you need shot to shot exposure consistency. If you did a bunch of portraits with a studio backdrop the Canon Wireless and E-TTL or E-TTL 2 is going to look at each shot and will decide on the exposure. Even small changes to exposure in this example will change the density and even colour of the backdrop and will require many hours in Photoshop to fix it. For this type of assignment I much prefer to use manual monolights that I can measure and set up with a flash meter and that DO give me shot to shot to shot consistency.

But for photojournalistic feature photos, press conferences or any situation that doesn't require this shot to shot consistency then the Canon Wireless is brilliant. Leave a message for me on this site and I'll send you some shots if you'd like.

dpp
24th of November 2004 (Wed), 07:53
PM sent

caldgrp
24th of November 2004 (Wed), 08:27
[What the Canon Wireless System isn't particularly good for is when you need shot to shot exposure consistency. If you did a bunch of portraits with a studio backdrop the Canon Wireless and E-TTL or E-TTL 2 is going to look at each shot and will decide on the exposure. Even small changes to exposure in this example will change the density and even colour of the backdrop and will require many hours in Photoshop to fix it. For this type of assignment I much prefer to use manual monolights that I can measure and set up with a flash meter and that DO give me shot to shot to shot consistency.]

Is this lack of consistency also true if you use Manual exposure? I had assumed that E-TTL set the flash for the portrait subject while the Manual setting would result in a consistent background exposure through a series of shots.

Jon
24th of November 2004 (Wed), 08:36
Are you asking about manual mode on the camera or the flash? Setting the flash on manual will give you exactly the working conditions of regular manual strobes (except your 420EX won't play). Setting the camera on manual will give you ETTL on the subject while the background will get the manual exposure, plus whatever spill the flash provides.

caldgrp
24th of November 2004 (Wed), 08:43
Are you asking about manual mode on the camera or the flash? Setting the flash on manual will give you exactly the working conditions of regular manual strobes (except your 420EX won't play). Setting the camera on manual will give you ETTL on the subject while the background will get the manual exposure, plus whatever spill the flash provides.

Sorry for the ambiguity. I was referring to Manual on camera. Will the manual exposure on the background address Dave's point about inconsistency

Jon
24th of November 2004 (Wed), 08:55
Sort of depends, like I said, on how much spillover from the flash onto the background there is. If the subject and background have a reasonable separation, there won't be as much of a problem as if there's minimal (1-3 ft for a portrait, say) separation between them. Ideally, for minimum flash influence on the background the flash-subject distance will be on the order of 1/2 the flash-background distance.

DaveG
24th of November 2004 (Wed), 09:06
[What the Canon Wireless System isn't particularly good for is when you need shot to shot exposure consistency. If you did a bunch of portraits with a studio backdrop the Canon Wireless and E-TTL or E-TTL 2 is going to look at each shot and will decide on the exposure. Even small changes to exposure in this example will change the density and even colour of the backdrop and will require many hours in Photoshop to fix it. For this type of assignment I much prefer to use manual monolights that I can measure and set up with a flash meter and that DO give me shot to shot to shot consistency.]

Is this lack of consistency also true if you use Manual exposure? I had assumed that E-TTL set the flash for the portrait subject while the Manual setting would result in a consistent background exposure through a series of shots.

You can only use the Manual setting if you have two 550's. The 420 is incapable of being set onto manual. As such I have no experience using it this way.

scottbergerphoto
24th of November 2004 (Wed), 11:23
Two articles on this in the EOS Flash Sticky.
Scott

DaveG
24th of November 2004 (Wed), 12:23
Sort of depends, like I said, on how much spillover from the flash onto the background there is. If the subject and background have a reasonable separation, there won't be as much of a problem as if there's minimal (1-3 ft for a portrait, say) separation between them. Ideally, for minimum flash influence on the background the flash-subject distance will be on the order of 1/2 the flash-background distance.

I think that if any part of the shot is left on E-TTL then there are going tobe inconsistencies. Even if the background stays exactly the same from shot to shot, any change in exposure for the subject's face will mean that you will try to do Photoshop levels and so forth based on the face. This in turn will have an effect on the background unless you use a selction tool to isolate the background. This is still the same amount of work that I don't want to do if I can avoid it.

DaveG
24th of November 2004 (Wed), 12:24
PM sent

Didn't get it.